Catalyst prepared by steaming alkali metal aluminosilicate in a matrix with polyvalent metal salt



hired CATALYST PREPARED BY STEAli IING ALKALI METAL ALUMINOSKLICATE IN AMATRIX WITH POLYVALENT METAL SALT Charles J. Plank, Woodbury, and EdwardI. Rosinski, Deptford, N.J., assignors to Mobil Oil Corporation, acorporation of New York No Drawing. Continuation-impart of applicationSer. No. 492,309, Oct. 1, 1965. This application Mar. 7, 1967, Ser. No.621,138

The portion of the term of the patent subsequent to July 2, 1985, hasbeen disclaimed Int. Cl. B01 11/58 US. Cl. 252-455 13 Claims ABSTRACT OFTHE DISCLOSURE Active catalyst for cracking and other hydrocarbonconversions results from steaming a reaction mixture of alkali metalaluminosilicate with a polyvalent metal compound in a refractory porousoxide matrix. A suitable mixture is a synthetic sodium faujasite andrare earth chloride dispersed in kaolinite.

APPLICATIONS This application is a continuation-in-part of applicationer. No. 492,309, filed Oct. 1, 1965 and now abandoned; the same being acontinuation-in-part of application Ser. No. 379,813, filed July 2, 1964(now Patent No. 3,257,- 310), application Ser. No. 449,603, filed Apr.20, 1965 (now Patent No. 3,210,267), and application Ser. No. 466,096,filed June 22, 1965 (now Patent No. 3,271,418). Application Ser. No.621,144, filed concurrently herewith, claims catalysts herein disclosedand prepared by steaming of high silica alkali metal zeolites mixed withmatrix material.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to a new and improved cracking catalyst characterized by unusualability to selectively crack high molecular weight hydrocarbon oils tolighter material boiling in the gasoline range. In one embodiment, theinvention is concerned with a catalyst composition comprising thereaction product of a crystalline alkali metal aluminosilicate with apolyvalent metal compound and an inorganic oxide matrix whereininteraction of the aluminosilicate and matrix components is controlledto produce a highly active and selective catalyst. In anotherembodiment, the invention is directed to a method for producing suchcatalyst.

Description of the prior art Catalyst of enhanced activity and having amarkedly superior selectivity for production of gasoline by cracking ofhigh boiling hydrocarbons has been widely adopted following thediscoveries described in US. patents such as 3,140,249 (Plank et al.,July 7, 1964) and 3,257,310 (Plank et al., June 21, 1966). As shown inthe earlier of these patents, crystalline alumino-silicates in suchporous matrices as silica-alumina gels and equivalent refractory poroussolids known to the catalytic cracking art are unusually effectivecracking catalysts when so treated as to have low content of alkalimetal. Effective treatments there shown include base exchange withaqueous solutions which contain cations capable of replacing theoriginal alkali metal content of the aluminosilicates. The later patentreveals benefits obtained by steam treatment of such composites.

e g is SUMMARY OF THE INVENTION This invention provides a technique forthe preparation of highly active catalysts of excellent stability tosteam, hence high stability under reaction conditions in which thecatalyst is exposed to high temperature steam atmospheres as in manytypes of commercial catalytic cracking plants. The new method operateson aluminosilicates which are inherently unstable to steam due toconcentration of alkali metal cations. Such high alkali metalaluminosilicates are combined with polyvalent metal compound andinorganic oxide matrix material, preferably of high alumina content, toform a reaction mixture which is subjected to the action of steam. Inthese reaction mixtures, the agent which is normally destructive ofthese alkali metal aluminosilicates converts the same to a highlyactive, steam-stable catalyst.

DESCRIPTION OF SPECIFIC EMBODIMENTS In accordance with the presentinvention, it has been discovered that highly active and stable crackingcatalysts can be prepared from crystalline alkali metal aluminosilicatesby thermally interacting the aluminosilicate with an inorganic oxidematrix so as to achieve fixation of alkali metal cations within thematrix component. It has been discovered that stability can be obtainedwithout necessitating pre-exchange of an alkali metal aluminosilicate byproviding a sink for irreversible removal of alkali metal into a secondcomponent of the catalyst composite itself. Thus, when an alkali metalcrystalline aluminosilicate is mixed with an inorganic oxide matrix andthermally interacted in the presence of steam as hereinafter defined,the alkali metal migrates irreversibly into the inorganic oxide matrixand becomes insoluble. While the total alkali metal content of thecomposite remains the same and may be high, i.e., greater than 1 weightpercent, the amount of exchangeable alkali metal in the composite isbelow about 0.6 weight percent and excellent stability is achieved. Incontradistinction to previous methods for preparing highly activecrystalline aluminosilicate catalysts wherein the alkali content of thealuminosilicate has been minimized and reduced by substantialreplacement to obtain steam-stable compositions, the present inventionprovides a means whereby the as-synthesized or unstable alkali metalform of the crystalline aluminosilicate can be used directly to obtainstable catalyst composition of unusually high catalytic activity andselectivity. The enhanced activity of the catalyst is dependent uponcontrolled interaction of the crystalline alkali metal aluminosilicatezeolite with the inorganic oxide matrix so as to achieve fixation andirreversible migration of alkali metal cations Within the matrixcomponent. The unusual use of the matrix material in accordance with theinvention serves to provide a dual effect of rendering alkali metalcations inactive and contributing unique properties to the resultingcombination which are not possessed by either component alone.

The present invention is concerned in one aspect with a method for thepreparation of a catalyst composition comprising an alkali metalcrystalline aluminosilicate zeolite and an inorganic oxide matrixwherein the catalyst is prepared by forming a mixture of bothcomponents, thermally reacting the mixture at temperatures of at least800 F. in the presence of steam for a period of at least one-half hour,and thereafter recovering the resulting product, said product beingcharacterized by having less than 0.6 weight percent, based on the totalcomposite, of exchangeable alkali metal when treated with excess 25percent aqueous ammonium chloride solution at 180 F. for 24 hours.

The aluminosilicates used for purposes of the invention arebase-exchangeable alkali metal or alkali metal-containing crystallinealuminosilicates which are unstable to steam. As defined herein,unstable to steam means that such aluminosilicate will lose greater than50 percent and usually more than 70 percent of its rigidthree-dimensional structure as defined by X-ray crystallinity, sorptioncapacity and/or surface area, when treated with 100 percent steam at1200 F. for 24 hours under a pressure of 15 p.s.i.g. Aluminosilicatesmeeting this definition include the as-synthesized or alkali metal formsas well as alkali metal-containing aluminosilicates which have beenpartially pre-exchanged with one or more cations to reduce the originalalkali metal content. As an example, alkali metal aluminosilicateshaving the crystallographic structure of faujasite, such as zeolites Xand Y, contain approximately 14 weight percent and weight percentsodium, respectively, and will lose at least 99 percent of their surfacearea when treated with steam under the conditions above defined.Similarly, when the alkali metal form of zeolite Y is base-exchangedwith rare earth cations and partially reduced to a sodium level of 4.3Weight percent, 75 percent of its surface area is lost upon steaming. Ata sodium level of 6 weight percent, a 97 percent loss of surface area isobtained. Similarly, when the sodium level of zeolite X is reduced to5.9 Weight percent with rare earth cations, a 98 percent loss of surfacearea is obtained upon steaming. As a general guide, it may be statedthat base-exchangeable crystalline aluminosilicates which contain atleast 4 weight percent alkal metal are unstable to steam within thedefinition above described. As a result of being unstable to steam, suchaluminosilicates are extremely poor catalysts for the conversion ofhydrocarbons.

The crystalline aluminosilicates utilized in accordance with theinvention may be expressed in terms of oxide mole ratios whichcorrespond to the general formula:

wherein M represents an alkali metal cation; M represents a polyvalentmetal having a valence of n; x is a number such that the alkali metalcontent is at least 4 weight percent; w is a number between 2 and 20representing the moles of SiO;;, and y the moles of H 0. Many of thesealuminosilicates are found in nature, for example, chabazite anderionite; while others, such as zeolites A, X, L and Y, may besynthesized by reacting silica and alumina with caustic at temperaturesof about 100 C. for periods of minutes to 90 hours or more. Thealuminosilicates are essentially the dehydrated forms of crystallinehydrous siliceous zeolites containing varying quantities of alkali metaland aluminum with or without other metals. The alkali metal atoms,silicon, aluminum and oxygen in these zeolites are arranged in the formof an aluminosilicate salt in a definite and consistent crystallinepattern and may be base-exchanged with numerous cations. The structurecontains a large number of small cavities, interconnected by a number ofstill smaller holes or channels. The alkali metal-containingaluminosilicates used in preparation of the present catalyst have auniform pore structure comprising openings characterized by pores havingopenings of uniform size greater than 4 and less than 15 angstrom units,the pore openings being sufiiciently large in three dimensions to admitthe molecules of the hydrocarbon charge desired to be converted. Thepreferred crystalline aluminosilicates will have a rigidthree-dimensional network characterized by a system of cavities andinterconnecting ports or pore openings, the cavities being connectedwith each other in three dimensions by pore openings or ports which haveminimum diameters of at least 6 angstrom units.

Aluminosilicates falling within the scope of the above formula are wellknown and include synthetic materials designated as zeolites Y, A, L, Tand X and natural aluminosilicates such as gmelinite, erionite,faujasite and chabazite. The useful aluminosilicates have a sorptioncapacity at 760 millimeters and 25 C. of at least 4 weight percent ofnormal butane. Particularly preferred materials are the crystallinealkali metal aluminosilicates which have a silica to alumina mole ratioof at least 2.3 and a pore size of between 6 and 15 angstrom units.

Pursuant to the teachings of the invention, the alkali metalaluminosilicate is combined, dispersed or otherwise intimately admixedwith an inorganic oxide matrix which, under the thermal conditionshereinbelow described, is capable of interacting with thealuminosilicate so as to achieve fixation and irreversible migration ofalkali metal cations within the matrix component. The inorganic oxidematrix which can be employed for this purpose is capable of wideselection and may be amorphous, crystalline or a material which is bothcrystalline and amorphous.

Typical matrix components are the alumina-containing siliceous inorganicoxides which occur naturally, such as the various clay minerals.Representative clays include attapulgite, kaolin, sepiolite,polygarskite, kaolinite, bentonite, montmorillonite, illite, chlorite adhalloysite. Of the foregoing, the preferred materials are thetwo-layered clays such as the members of the kaolinite group, i.e.,kaolinite, dickite, nacrite, and halloysite. The clay materials may beutilized directly in their natural or raw state, or may be previouslywater-washed, acid-treated, caustic-treated, calcined or otherwisetreated prior to mixing with the aluminosilicate.

Other preferred matrix materials are the alumina-containing inorganicoxides which are prepared by synthetic formulation of composites ofalumina with a hydrous inorganic oxide of at least one metal selectedfrom the group consisting of metals of Groups II-A, III-B and IVA of thePeriodic Table. Such components include, for example, silica-alumina,alumina-zirconia, aluminatitania, alumina-beryllia, as well as ternarycombinations such as silica-alumina-thoria, silica-alumina-zirconia, andsilica-alumina-magnesia. Particular preference is accorded syntheticcomposites of silica-alumina, alumina-zirconia andsilica-alumina-zirconia. In the foregoing composites alumina isgenerally present as the minor component and the other oxides of metalsare present in major proportion. Thus, the alumina content of suchcomposites is generally within the approximate range of at least 10weight percent, preferably 15 to 55 weight percent, with the otherhydrous inorganic oxide content ranging from 45 to weight percent. Whenthe inorganic oxide matrix is an amorphous material such as a compositeof alumina with a hydrous inorganic oxide of a metal, such as abovedescribed, a high alumina content, e.g., 15 to 55 weight percent,preferably 25 to 55 Weight percent, is desired in order to facilitatefixation of the alkali metal cations within the matrix component.Additionally, such composites are preferably prepared in the form of afinely divided homogeneous precipitate or co-gel by techniques which arewell known in the art.

The alkali metal aluminosilicate is dispersed, combined or otherwiseadmixed intimately with the matrix compo nent in any desired manner suchas in a ball mill, pulverizer, jet mill, muller mixer or the like. Themixing operation can be effected with dry materials, or in the presenceof an aqueous or non-aqueous medium, e.g., water or an inert solventsuch as benzene. The alkali metal aluminosilicate usually has a particlesize of less than 40 microns, preferably less than 10 microns, and ismixed with the inorganic oxide matrix in the form of a slurry. Themixture can be then extruded, pelleted or otherwise agglomerated toobtain uniform or irregularly shaped particles which may vary in sizefrom 20 microns to 4 inch in diameter. Following the formation ofpellets the composite is dried, if necessary, to remove substantiallyall the liquid therefrom. While drying may be effected at ambienttemperatures, it is more satisfactory to facilitate the removal ofliquid by maintaining the composition at a temperature between about F.and 1000 F. for 4 to 48 hours.

As hereinafter shown, it is a critical feature of the invention that theinorganic oxide matrix component be present in the final composite in anamount sufiicient to achieve fixation and irreversible migration ofalkali metal cations within the matrix component when thealuminosilicate and matrix component are subsequently thermallyinteracted. When the as-synthesized or alkali metal form of thealuminosilicate is employed, the matrix component must be used in anamount corresponding to at least 50 percent by weight, and preferably 70percent by weight or more, based on the final composite. Whenaluminosilicates are used which have been partially pre-exchanged withone or more polyvalent cations to reduce the original alkali metalcontent, the matrix component may be used in an amount as small as 40percent by weight, based on the final composite. In this embodiment,less matrix is required since the partially exchanged aluminosilicateeven though unstable to steam, i.e., containing at least 4 percent byweight alkali, contains a lesser amount of alkali metal cations forfixation within the matrix component. The amount of aluminosilicateemployed will be less than 60 weight percent and preferably less than 25weight percent, based on the final composite.

After formation of the composite, the alkali metal aluminosilicate andmatrix component are thermally interacted with one another at elevatedtemperatures of at least 800 5., preferably 1100 F. or higher, in thepresence of steam for a period of at least one-half hour. As will appearfrom data set forth hereinafter, the exposure of the catalyst compositeto thermal conditions in the presence of steam serves to render alkalimetal cations harmless by effecting fixation and irreversible migrationof the alkali metal cations within the framework of the matrixcomponent. The thermal interaction may be accomplished at temperaturesranging from 800 F. up to the decomposition temperature of theparticular aluminosilicate employed, which is generally less than about1600 F., in an atmosphere consisting of a substantial amount of steamranging from 5 to 100 percent by voltime. The steam treatment may beeffected at subatmos pheric, atmospheric or superatmospheric pressures.Thermal interaction is controlled to achieve fixation of the alkalimetal cations so that the final composite contains less than 0.6 weightpercent, preferably less than 0.4 weight percent, based on the finalcomposite, of exchangeable alkali metal. At a temperature of 1200" F.under a steam pressure of 1 atmosphere for a period of 1 hour thecomposite will contain less than 0.6 weight percent exchangeable alkalimetal as determined by base exchange with an excess of 25 percentaqueous ammonium chloride solution at 180 F. for 24 hours. By increasingthe period of time, however, e.g., from 2 to 25 hours or more, thecomposite will contain less than about 0.4 weight percent and maycontain less than 0.2 weight percent exchangeable alkali metal. Thepreferred temperature range thus ranges from at least 1100 F. for aperiod of at least one-half hour in the presence of steam underatmospheric pressure.

In general, control of the fixation operation can be readily achieved byconducting steaming of the' reaction mixture as a step in the catalystmanufacturing process before applying the product to use as a catalyst.In the alternative, this final step can be conducted in the equipment inwhich the catalyst is to be employed. For example, it is common practiceto operate many types of catalytic cracking units under conditions whichprovide steam atmospheres of adequate concentration at various points.The charge stock may be admitted to the reactor admixed with steam.Steam may be employed as purging or sealing medium, or both, betweenreactor and regenerator. Indeed, the regenerator may, itself, provideadequate concentration of steam as a sum of moisture in the air plusthat generated by line burner, if any, and that resulting from hydrogencontent, if any, of the coke burned from the catalyst in regeneration.The requisite time of steaming need not to be one uninterrupted period,but may be the accumulation of successive shorter intervals. Theessential feature is that the agent normally destructive of thecatalytic agent may, in a proper reaction mixture, be the essentialstabilizing agent. Thus, an effective mode of applying the invention isto supply the raw reaction mixture as make-up to an operating catalyticcracker.

The method heretofore described is applicable, with or withoutmodification, to treatment of aluinosilicates of high silica content, aratio of silicon to aluminum of at least about 1.5.

In a modification usable regardless of silicon to aluminum ratio of thealuminosilicate, various metal compound promoters can be incorporatedwithin the aluminosilicare-matrix reaction mixture for the purpose ofenhancing catalytic behavior of the final catalyst product. Preferredpromoters are salts and oxides of polyvalent metals such as aluminum,manganese, magnesium, calcium rare earth, iron, chromium and the like.The preferred compounds are the salts of the rare earths, particularlythe rare earth chlorides. The amount of promoter may range from 0 to 25weight percent based on the final catalyst composite and is preferablywithin the range of 0.5 to 15 weight percent.

Cracking, utilizing the catalyst described herein, may be carried out atcatalytic cracking conditions employing a temperature within theapproximate range of 700 F. to 1200 F. and under a pressure ranging fromsubatmospheric pressure up to several hundred atmospheres. The contacttime of the oil with the catayst is adjusted in any case according tothe conditions, the particlar oil feed and the particular resultsdesired to give a substantial amount of cracking to lower boilingproducts. Cracking may be effected in the presence of the instantcatalyst utilizing well-known techniques including, for example, thosewherein the catalyst is employed as a fluidized mass, fixed bed, or as acompact particle-form moving bed.

The catalysts of the present invention are specially suitable for use inboth the moving-bed and fluid cracking processes. In the moving-bedprocess (e.g., Thermofor Catalytic Cracking or TCC), catalyst particlesare used which are generally in the range of about 0.08 to 0.25 inch indiameter. Useful reaction conditions include temperatures above about850 F., pressures from subatmospheric to approximately 3 atmospheres,catalyst to oil ratios of about 1.5-15 and liquid hourly spacevelocities of about 0.5 to 6. In the fluidized catalytic crackingprocess (or FCC) catalyst particles are used which are generally in therange of 10 to 150 microns in diameter. The commercial FCC processesinclude one or both of two types of cracking zones-a dilute bed (orriser) and a fiuid (or dense) bed. Useful reaction conditions in fluidcatalytic cracking include temperatures above 850 F., pressures fromsubatmospheric to 3 atmospheres, catalyst-to-oil ratios of 1 to 30, oilcontact time less than about 12 to 15 seconds in the riser, preferablyless than about 6 seconds, wherein up to percent of the desiredconversion may take place in the riser, and a catalyst residence (orcontact) time of less than 15 minutes, preferably less than 10 minutes,in the fluidized (or dense) bed.

The catalysts described herein may also be used to catalyze a widevariety of different organic conversion processes other than cracking. Atypical example is the use of such catalysts for hydrocrackinghydrocarbon fractions such as gas oils, residual oils, cycle stocks,whole topped crude and heavy hydrocarbon fractions derived by thedestructive hydrogenation of coal, tars, pitches, asphalts, and thelike. The hydrogenation component can include metals, oxides andsulfides of metals of the Periodic Table which fall in Group V includingvanadium, Group VI including chromium, molybdenum, tungsten and thelike, and Group VIII including cobalt, nickel, platinum, palladium,rhodium and the like, and combinations of metals, sulfides and oxides ofmetals of the foregoing such as nickel-tungsten sulfide,cobalt-molybdenum oxide, cobalt-molybdenum sulfide and the like. Theamount of hydrogenation component can range from about 0.1 to about 30weight percent based on the catalyst. The hydrogenation component may becombined with the catalyst composite in any feasible manner, such asimpregnation, coprecipitation, cogellation, mechanical admixture and thelike. The hydrocracking operation is generally carried out at atemperature between about 400 F. and about 950 F. The hydrogen pressurein such operation is generally Within the range of about 100 and about3000 p.s.i.g. and, preferably, about 350 to about 2000 p.s.i.g. Theliquid hourly space velocity, i.e., the liquid volume of hydrocarbon perhour per volume of catalyst is between about .1 and about 10. Ingeneral, the molar ratio of hydrogen to hydrocarbon charge employed isbetween about 2 and about 80, and preferably between about 5 and about50.

The following examples illustrate the best mode now contemplated forcarrying out the invention. In each of the following catalystpreparations, the compositions were dried at 1000 F. for hours prior tothermal interaction. In each example where exchangeable sodium is shown,this was determined on a small test sample. A S-gram sample of thecatalyst was contacted for 24 hours at 180 F. with 20 grams of a 25%solution of NH Cl. After washing free of chloride ions, the sample wasdried and calcined and the sodium content determined. Calculations weremade by subtracting the sodium content of the exchanged sample from thatof the original sample. Catalytic data were obtained on the remainder ofthe example.

The following examples illustrate the use of various inorganic oxidematrices which can be used in accordance with the invention.

Example 1 In the preparation of this example, 48.4 grams of sodiumfaujasite (Si/Al 1.5; 78.4% solids) were mixed with 182 grams ofhalloysite clay (83.2 weight percent solids) and 450 cc. water for 2minutes in a blender. The slurry, after being dried to remove the liquidphase, was thermally treated at 1200/ F. with 100% steam for 24 hoursunder a pressure of p.s.i.g. The composite analyzed 1.7 weight percentsodium. After treating a test sample of the composite with an excess of25% aqueous ammonium chloride solution at 180 F. for 24 hours, thesample analyzed 1.66 weight percent sodium.

Example 2 In the preparation of this example, a ZrO A1 0 matrix wasfirst prepared by mixing 228 grams Zr (SO .4H O and 655 grams Al (SO.18H O and 1800 cc. H 0 and then precipitating the solution with NH OHto 6.2 pH using 529 cc. NH OH (29.9 weight percent NH This precipitatewas washed free of sulfate ion, then air dired at room temperature. To437.8 grams of this hydrous material (63.3 grams solids) was added 54.7grams of sodium faujasite (Si/Al 1.5; 50.5% solids) and 590 cc. water ina blender. The resulting slurry, after being dried to remove the liquidphase, was thermally treated at 1225 F. with 100% steam for hours atatmospheric pressure. The composite analyzed approximately 1.0 weightpercent sodium. After treating a test sample of the composite with anexcess of aqueous ammonium chloride solution at 180 F. for 24 hours, thesample analyzed 0.48 weight percent sodium.

The cracking activity of the catalyst composites prepared in Examples 1and 2 is illustrated in Table 1 below by their ability to catalyze theconversion of a Mid-Continent gas oil having a boiling range of 450F.950 F. to gasoline having an end point of 410 F. Vapors of the gas oilare passed through the catalyst at a temperature of about 900 F.,substantially at atmospheric pressure, at a feed rate of 2.0 to 4.0volumes of liquid oil per volume of catalyst per hour for ten minutes.The method of measuring the catalyst was to compare the various productyields obtained with such catalyst with yields of the same productsgiven by conventional silica-alumina catalyst at the same conversionlevel. The differences (delta values) shown hereinafter represent theyields given by the present catalyst minus yields given by aconventional silica-alumina catalyst.

The catalytic results summarized in Table 1 clearly demonstrate that thecomposition prepared in accordance with the invention are highly activeand selective in producing more (3 gasoline than the standardsilica-alumina reference catalyst.

TABLE 1 Example 1 2 Composition:

Na, wt. percent 1. 70 1. 0 Na, wt. percent after exchange- 1. 66 0. 48Na, wt. percent exchangeable" 0. 04 0. 52 Catalytic Evaluation:

Conditions:

LHSV 4 2 C/O 1. 5 3 Conversion, vol. percent" 73.1 71. 7 05+ gasoline,vol. percent 61. 4 54. 2 Total 085, vol. percent 15.4 16. 5 Dry gas, wt.percent 6. 7 7. 3 Coke, wt. percent 2. 0 4. 7 Ht, Wt. percent 0. 03 0.12Delta Advantage over Si/Al:

05+ gasoline, vol. percent +12. 8 +6. 1

Examples 3, 4 and 5 below illustrate the use of various types ofcrystalline aluminosilicates which can be employed in accordance withthe invention.

Example 3 In the preparation of this example, 29.5 grams (84.9% solids)of a crystalline aluminosilicate identified as zeolite L (1.0:L-0.l M:Al O :6.4:0.5 SiO were added with 258 grams of McNamee kaolin clay(87.4 weight percent solids) to 600 cc. water and mixed for 2 minutes ina blender. The resulting slurry, after being dried to remove the liquidphase, was thermally treated at 1200 F. with steam for 24 hours under apresure of 15 p.s.i.g. The composite analyzed 1.7 weight percent sodium.After treating a test sample of the composite with an excess of 25aqueous ammonium chloride solution at F. for 24 hours, the sampleanalyzed 1.22 weight percent sodium.

Example 4 In the preparation of this example, 25.9 grams of acrystalline aluminosilicate identified as zeolite X (Si/Al 1.5; 96.8%solids) were blended with 277 grams raw halloysite clay (81.3% solids)and 600 cc. water in a blender for 2 minutes. The resulting slurry,after being dried to remove the liquid phase, was thermally treated at1225 F. with 100% steam for 20 hours at atmospheric pressure. Thecomposite analyzed approximately 1.44 weight percent sodium. Aftertreating a test sample of the composite with an excess of 25 aqueousammonium chloride solution at 180 F. for 24 hours, the sample analyzed1.42 weight percent sodium.

Example 5 In the preparation of this example, 30.7 grams of acrystalline aluminosilicate (81.2% solids) identified as zeolite ZSM3were blended with 257 grams McNamee kaolin clay (87.4% solids) and 600cc. water in a blender for 2 minutes. The resulting slurry, after beingdried to remove the liquid phase, was thermally treated at 1225 F. with100% steam for 20 hours at atmospheric pressure. The composite analyzedapproximately 1.0 weight percent sodium. After treating a test sample ofthe composite with an excess of 25% aqueous ammonium chloride solutionat 180 F. for 24 hours, the sample analyzed 0.8 weight percent sodium.

TABLE 2 Example 3 4 Composition:

Na, wt. percent 1. 7 1. 44 1.0 Na, wt. percent after exchange 1. 22 1.42 0.8 Na, wt. percent exchangeable 48 02 0.2 Catalytic Evaluation:

Conditions:

L SV 2 4 4 a 1. 5 1. 5 Conversion, vol. percent.-. 35.1 44. 55.2gasoline, vol. percent 29. 5 39.1 48. 4 Total C4s, vol. percent 6. 2 8.211.2 Dry gas, wt. percent. 3. 7 3. 8 4.3 Coke, wt. percent 1. 6 1.0 1.1He, wt. percent 0.18 0.02 0.06 Delta Advantage Over C5+ gasoline, vol.percent +1. 7 +5 9 +8. 5

Examples 6, 7 and 8 illustrate the use of steam-unstable alkali metalaluminosilicates in which the original sodium cations have beenpartially exchanged with other metal cations.

Example 6 In this example, 59.8 grams of a partially exchanged rareearth zeolite X aluminosilicate (6.3 weight percent Na) were mixed with229 grams McNamee kaolin clay and 600 cc. water for 2 minutes in ablender. The resulting slurry, after being dried to remove the liquidphase was thermally treated at 1225 F. with 100% steam for 20 hours atatmospheric pressure followed by a second thermal treatment at 1200 F.with 100% steam for 24 hours under a pressure of 15 p.s.i.g. The productanalyzed 0.84 weight percent sodium. Upon treating a test sample of thecomposite with an excess of 25% aqueous ammonium chloride solution at180 F. for 24 hours substantially no sodium was removed from the sample.

Example 7 In this example, a partially exchanged calcium zeolite Xaluminosilicate (6.3 weight percent Na) was mixed with McNamee kaolinclay in the same manner as Example 6. The sample analyzed 1.3 weightpercent sodium and upon treating a test sample of the composite withexcess ammonium chloride solution substantially no sodium was removedfrom the sample.

Example 8 TAB LE 3 Example Composition:

Na, wt. percent Na, wt. percent exchangeable Catalytic Evaluation:

Conditions:

Conversion, vol. percent 05+ gasoline, vol. percent Total Ois, vol.percent Dry gas, wt. percent- Coke, wt. percent n r rg r m ear-mucousrewr H gbowawv uuh HO DOCUIDF He, wt. percent Delta Advantage Over Si/Al:

05+ gasoline, vol. percent Examples 9 through 15 illustrate varioustypes of metal salt promoters which can be employed in the preparationof the catalyst compositions of the invention.

Example 9 In the preparation of this example, 25.9 grams of acrystalline aluminosilicate identified as zeolite X (96.8 wt. percentsolids) was mixed with 18.65 grams of rare earth chloride hexahydrate,257 grams of McNamee kaolin clay (87.4% solids) together in 600 cc.Water for two minutes in a blender. The resulting slurry, after beingdried to remove the liquid phase, was thermally treated at 1200" F. with100% steam for 24 hours under a pressure of 15 p.s.i.g. The productanalyzed 1.3 wt. percent sodium. After treating a test sample of thecomposite with an excess of 25 aqueous ammonium chloride solution at 180F. for 24 hours, the sample analyzed 1.23 wt. percent sodium.

Example 10 In the preparation of this example, 30.1 grams of sodiumfaujasite (Si/Al 1.5; 83% solids) was mixed with 11.1 grams of rareearth chloride hexahydrate, 258 grams of McNamee kaolin clay together in600 cc. Water for two minutes in a blender. The resulting slurry, afterbeing dried to remove the liquid phase, was thermally treated at 1200 F.with 100% steam for 24 hours under a pres sure of 15 p.s.i.g. Theproduct analyzed 0.75 wt. percent sodium. Upon treating a test sample ofthe composite with an excess of 25% aqueous ammonium chloride solutionat 180 F. for 24 hours, substantially no sodium was removed.

Example 11 This example was prepared in a manner identical to Example10, using the same procedure and amounts of sodium faujasite, clay andrare earth salt. Instead of mixing in water, benzene was used. Theproduct analyzed 1.0% sodium. After treating a test sample of thecomposite with an excess of 25 aqueous ammonium chloride solution at 180F. for 24 hours, the sample analyzed 0.98 wt. percent sodium.

Example 12 In the preparation of this example, 29.5 grams of acrystalline aluminosilicate identified as sodium faujasite (Si/Al 1.5;85% solids) was mixed with 11.5 grams Cr(NO '9H O, 257 grams McNameekaolin clay in 800 cc. of benzene for two minutes in a blender. Theresulting slurry, after being dried to remove the liquid phase, wasthermally treated at 1225 F. with steam for 20 hours under atmosphericpressure. The product analyzed 1.04 wt. percent sodium. After treating atest sample of the composite with an excess of 25 aqueous ammoniumchloride solution at F. for 24 hours, the sample analyzed 0.77 wt.percent sodium.

Example 13 This example was prepared in a manner identical to Example 12except that the metal salt employed was 6.95 grams of ZrOCl -8H O. Theproduct analyzed 0.94 wt. percent sodium. After treating a test sampleof the composite with an excess of 25 aqueous ammonium chloride solutionat F. for 24 hours, the sample analyzed 0.79 wt. percent sodium.

Example 14 This example was prepared in a manner identical to Example 12except that the metal salt employed was 8.75 grams of MgCl -6H O. Theproduct analyzed 1.02 wt. percent sodium. After treating a test sampleof the composite with an excess of 25% aqueous ammonium chloridesolution at 180 F. for 24 hours, the sample analyzed 0.97 wt. percentsodium.

Example 15 This example was prepared in a manner identical to Example 12except that the metal salt employed was 8.53 grams of MnCl -6H O. Theproduct analyzed 0.95 wt. percent sodium. After treating a test sampleof the composite with an excess of 25% aqueous ammonium chloridesolution at 180 F. for 24 hours, the sample analyzed 0.89 wt. percentsodium.

The catalytic evaluation of the data shown in Table 4 again illustratesthe exceptional activity and selectivity These two solutions were mixedtogether along with Maresperse compound to aid in dispersing the slurry.The final silicate solution had a specific gravity of 1.324 at 70 F.

Acid solution of the catalyst composltrons prepared in accordance with 520.6 lbs. water the rnvention. 3.03 lbs. Al (SO l8H O TABLE 4 Example 910 11 12 13 14 15 Composition:

Na, wt. percent 1. 3 0. 75 1. 0 04 0. 04 1. 12 0. 95

Na, wt. percent after exchange- 1 23 0 98 0. 77 0. 79 0. 97 0. 89

Na, wt. percent exchangeable. 07 nil 02 27 15 .05 06 CatalyticEvaluation:

Conditions:

LHS 4 4 4 4 4 4 4 (3/0 1.5 1.6 1.5 1.5 1.5 1.5 1.5

Conversion, vol. percent 65. O 72. 5 62. 1 67. 8 71.8 74.3 72. 4

05+ gasoline, vol. percent- 55. 2 62.4 54. 7 57. 8 58. 4 62. 7 61. 0

Total C4s, vol. percent- 12. 4 14. 6 12. 2 14. 1 16. 3 15. 1 15.3

Dry gas, wt. percent 5. 8 5. 8 5. 2 6.1 7. 6 6. 8 6. 7

Coke, wt. percent... 2.4 2.0 0. 0 1. 5 1. 9 2.1 1. 8

H2, wt. percent- 0. O8 0. 05 G. 04 0. 05 0. 11 0. O5 0. 07 DeltaAdvantage Over Si/Al:

05+ gasoline, vol. percent +10. 2 +14. 0 +11. 2 +11.4 +103 +13. 6 +12. 7

The following Examples 16 to 18 illustrate that the 1.38 lbs. H 80 97.6wt. percent catalyst compositions of the invention can be prepared inpreformed shapes for use in commercial units.

Example 16 In this example, 289 grams of sodium faujasite (Si/Al l.5;51.8 solids), 862 grams of McNamee kaolin clay (87% solids) and 105.6grams bentonite clay (94.6% solids) were mixed together in a blenderadding 4000 cc. water. Nine pounds of this slurry was filtered and thenextruded hydraulically under 5 to 7 tons pressure through a die having 7holes. A portion of the wet extrudate was cut to about one-quarter inchin length and thermal- 1y treated at 1300 F. with 100% steam for 24hours at atmospheric pressure. The original sodium content of thecomposite was 1.7 wt. percent. After the thermal treatment, a testsample Was treated with an excess of 25 aqueous ammonium chloridesolution at 180 F. for 24 hours and the sample analyzed 1.36 wt. percentsodium.

Example 17 Example 18 This catalyst was made in bead form by mixing thefollowing solutions:

Silicate solution SiO 28.9 wt. percent Na O8.9 wt. percent H O62.2 wt.percent 8.72 lbs. Q brand silicate 4.36 lbs. Water 11.22 lbs. McNameekaolin clay 2.66 lbs. sodium faujasite (Si/Al 1.5; 51.8 wt. percentsolids) 1.62 lbs. water Sp. gr. 1.102 at 86 F.

The silicate and acid solutions were mixed together continuously adding302 cc. per min. silicate solution at F. with 190 cc. per min. acidsolution at room temperature. The resulting sol having a 10.1 pH and agel time less than one second was formed into particles by spraying thesol into air. The formed particles were subsequently processed by waterwashing free of soluble ions and then dried at 450 F.

The resulting composition, which analyzed 1.3 wt. percent sodium, wasthermally treated at 1200 F. with 100% steam for 24 hours under apressure of 15 p.s.i.g. After treating a test sample of the compositewith an excess of 25% aqueous ammonium chloride solution at 180 F. for24 hours, the sample analyzed 1.29 wt. percent sodium.

Table 5 below shows that the compositions prepared in Examples 16-18 areexcellent catalysts for cracking gas oil.

TABLE 5 Example 16 17 18 Com osition:

Na, wt. percent 1. 70 1. 70 1. 3 Na, wt. percent after exchange- 1.36 1. 51 1. 29 Na, wt. percent exchangeable.- 34 19 01 CatalyticEvaluation:

Conditions:

LHSV' 4 4 4 C/ 1. 5 1. 5 1. 5 Conversion, vol. percent 66.7 71.3 45. 9Crigasoline, vol. percent 56. 5 61. 7 41. 8 Total Gqs, vol. percent. 13.4 14. 0 7. 8 Dry gas, wt. percent. 5. 8 6. 0 3. 7 Coke, wt. percent. 1.8 1. 6 0.8 Ha, wt. percent 0.05 0.0 0. 06 Delta Advantage Over Si/Al:

05+ gasoline, vol. percent +10. 7 +13. 8 +7. 5

Examples 19-21 illustrate the use of varying amounts of the inorganicoxide matrix components and the effect thereof on catalytic behavior.

Example 19 In the preparation of this example, 93 grams of sodiumfaujasite (Si/Al l.5; 80.6% solids) was mixed with 201 grams McNameekaolin clay (87% solids) and 600 cc. water for 2 minutes in a blender.The resulting slurry, after being dried to remove the liquid phase, wasthermally treated at 1200 F. with 100% steam for 24 hours under apressure of 15 p.s.i.g. The product analyzed 2.6 wt. percent sodium.

Example 20 In the preparation of this example, 77.5 grams of sodiumfaujasite (Si/Al 1.5; 80.6% solids) was mixed 13 with 71.9 grams McNameekaolin clay (87% solids) and 300 cc. water for 2 minutes in a blender.The resulting slurry, after being dried to remove the liquid phase, wasthermally treated at 1200 F. with 100% steam for 24 hours under apressure of 15 p.s.i.g. The product analyzed 4.4 wt. percent sodium.

Example 21 In the preparation of this example, 19 1.5 grams of sodiumfaujasite (Si/Al 1.5; 78.4% solids) was mixed with 11.5 grams McNameekaolin clay (87.4% solids) and 600 cc. water for 2 minutes in a blender.The resulting slurry, after being dried to remove the liquid phase, wasthermally treated at 1200 F. with 100% steam for 24 hours under apressure of 15 p.s.i.g. The product analyzed 4.8 wt. percent sodium.

Table 6 below illustrates that when the as-synthesized or alkali metalform of the aluminosilicate is employed, the matrix component must beused in an amount corresponding to at least 50 percent by weight basedon the final composite.

TABLE 6 Example Composition:

Matrix c0110., wt. percent Na, wt. percent Catalytic Evaluation:

Conditions:

14 Example 23 In this preparation, a composite containing 30 weightpercent sodium faujasite (Si/Al 1.5) and 70 weight percent McNarnee claywas prepared in a manner similar to that described in Example 19, exceptthat the thermal interaction was carried out at 1225 F. with 100 percentsteam for 20 hours at atmospheric pressure. 246.2 grams 141.5 cc. ofammonium tungstate solution (0.203 gram tungsten/cc. solution) in a2-step operation to deposit 10 weight percent tungsten. The resultingproduct, after being dried at 230 F., was then impregnated with 141 cc.of solution containing 56.75 grams Ni(NO -6H O to deposit 4 weightpercent nickel. The final product was then dried for 20 hours at 230 F.and calcined for 10 hours at 1000 F.

Example 24 The particular sample of catalytic composite used in thistest was prepared by mixing 521 grams of sodium zeolite Y, dried at 230F. (51.8 weight percent solids), with 1090 grams of McNamee clay toconstitute a catalytic composite containing 20 weight percent activecomponent. 3270 cc. of water was used to aid in the dispersion. Themixing was carried out in a blender by mixing vigorously for 2 minutes.Following the mixing, the wet slurry was dried at 230 F., then pelletedand sized 4-10 mesh, calcined for 10 hours at 1000 F., and then chargedto an automatic cycling unit. In this cyclic unit, the catalyst wassubjected to alternate cracking and regeneration periods. The cyclictreatment was as follows:

Example 22 In this preparation, 47.9 grams of a crystallinealuminosilicate identified as sodium faujasite (Si/Al 1.5; 50.8 wt.percent solids) was mixed with 600 cc. water and 233 grams ofconvenional silica-alumina cracking catalyst (10% alumina) which hadbeen pulverized to less than 20 microns. The mixture was blended for 2minutes. The resulting slurry, after being dried to remove the liquidphase, was thermally treated at 1200 F. with 100% steam for 24 hoursunder a pressure of 15 p.s.i.g. The product analyzed 1.0 wt. percentsodium. After treating a test sample of the composite with an excess of25% aqueous ammonium chloride solution at 180 F. for 24 hours, thesample analyzed 0.66 wt. percent sodium. Catalytic evaluation of thecatalyst composite for cracking gas oil is shown below in Table 7.

The following example illustrates the preparation of a catalyst which isuseful for hydrocracking hydrocarbon fractions such as petroleum gasoils as previously described.

Pressure, 'Iemp., Time, Sequence Charging p.s.i.g. F. Stage min.

0 950 Regeneration 20 0 1,1501,200 -d 30 0 1,200-950 Cooling 15 0-15 950Pressuring to run 2 conditions. 15 950 Steam treat 10 15 950 Cracking 1015-0 950 Purge and 10 depressure.

*Steam was 5 weight percent of the oil.

The catalyst was initially evaluated at CAT-C conditions of 4 LHSV, 1.5C/O and at 9000 F. charging Wide Range Mid-Continent gas oil, and after70, 145, 217, 290 and 344 cycles as described above. Catalytic resultsare summarized as follows:

These data show that, in about 70 cycles of operation, the catalyticcomposite can be converted to yield catalytically selective composite.Continued cyclic treatment shows continued improvement in catalyticselectivity.

These data show that these catalytic solid-solid interactions can beaccomplished at conditions present in commercial units.

As shown above, catalysts of good initial activity can be prepared bysteaming blends of matrix material with zeolites of high or low silicacontent. However, it has been found that such blends of low silicazeolite are unstable unless polyvalent metal compound (oxide or salt) beadded to the reaction mixture. Thus, the general method (without addedmetal compound) produces good,

stable catalyst only with aluminosilicates of silicon to aluminum ratioat least as great as 1.5.

The data in Examples 25, 26 and 27, taken with Table 8, show that, usingkaolinite clay, the NaX product gave catalytic results even poorer than100 percent kaolinite (steam-treated in the same way) by itself. Thesodium zeolite Y, on the other hand, gave a very active and selectivecatalyst.

Example 25 A batch of kaolinite clay (McNamee) was pelleted, crushed andscreened to give a 500 cc. sample of 4-10 mesh particles. This materialwas calcined in air for 10 hours at 1000 F. Half the batch Was thentreated in 100 percent steam for 24 hours at 1200 F. and 15 p.s.i.g.prior to testing for gas oil cracking.

Example 26 A 26.1-gram portion of synthetic NaX zeolite (Linde 13X)(95.6 percent solids) and a 258-g'ram portion of kaolinite clay(McNamee) (87.4 percent solids) were mixed for 2 minutes with 600 cc. ofH in a Waring blender. The resulting slurry was dried overnight at 230F., pelleted, ground and screened to obtain 4-10 mesh particles, whichwere then calcined in air for 10 hours at 1000 F. The batch was thensplit in halves, One half was treated in 100 percent steam for 24 hoursat 1200 F. and 15 p.s.i.g. prior to testing for gas oil crackmg.

Example 27 TABLE 8 E xample 25 26 27 Sieve, percent 1 10 2 10 Kaolinite,percent 100 90 90 Gas Oil Cracking Data at 4.0 LHSV and 1.5 C/():

Conversion, vol. percent 22. 8 16. 3 59. 3 05+ gasoline, v01. percent..-21. 1 15. 0 51. 9 Total 04's, vol. percent--- 1. 7 l. 6 11. 7 Dry gas,wt. percent- 2.0 1. 6 4. 8 Coke, wt. percent- 0. 8 1.2 1. 2

l NaX. 2 NaY.

The data in Examples 28, 29 and 30, taken with Table 9, show that it ispossible to prepare a catalyst from NaX and halloysite having a moderateactivity (though less than the activity of conventional silica-alumina)and good selectivity. However, the stability of the catalyst is verypoor. After 72 hurs of pressure steaming, it gives a conversion of only29.5 percent, and halloysite clay by itself (after 72 hours of steaming)gives 20.3 percent conversion. The NaY catalyst, on the other hand,started with an extraordinarily high activity and selectivity, most ofwhich was retained after the steaming process.

Example 28 A 25.9-gram portion of synthetic NaX zeolite (Linde 13X)(96.8 percent solids) and a 277-gram portion of halloysite clay (81.3percent solids) were mixed for 2 minutes with 600 cc. of H 0 in a Waringblender. The resulting slurry was dried overnight at 230 F., pelleted,crushed and screened to obtain a batch of 4-10 mesh particles. Thismaterial was calcined in air for hours at 1000 F. After treating with100 percent steam for 20 hours at 1225 F. and atmosphere pressure, itwas tested for gas oil cracking. The results of this test are given inColumn 1, Table 9. It was then further treated with 100 percent steamfor 24 hours at 1200 F. and p.s.i.g.

and retested for gas oil cracking. The results of this test are given incolumn 2, Table 9. And, finally, the catalyst was further treated withpercent steam for an additional 48 hours (72 hours total) at 1200 F. and15 p.s.i.g. and again tested for gas oil cracking. The results of thistest are given in column 3, Table 9.

Example 29 A batch of halloysite clay pellets was crushed and screenedto obtain a 250 cc. sample of 4-10 mesh particles. This material wascalcined in air for 10 hours at 1000 F. It was then treated with 100percent steam for 72 hours at 1200 F. and 15 p.s.i.g. prior to testingfor gas oil cracking.

Example 30 A 54.4-gram portion of synthetic NaY zeolite (46 percentsolids) and a 277-gram portion of halloysite (81.3 percent solids) weremixed for 2 minutes with 600 cc. of H 0 in a Waring blender. Theresulting slurry was dried overnight at 230 F., pelleted, crushed andscreened to give a batch of 4-10 mesh particles. This material wascalcined in air for 10 hours at 1000 F. After treating with 100 percentsteam for 20 hours at 1225 F. and atmospheric pressure, it was testedfor gas oil cracking. The results of this test are given in column 5,Table 9. It was then further treated with 100 percent steam for 24 hoursat 1200 F. and 15 p.s.i.g. and retested for gas oil cracking. Theresults of this test are given in column 6, Table 9. And, finally, thecatalyst was further treated with steam for an additional 48 hours (72hours total) at 1200 F. and 15 p.s.i.g. and again tested for gas oilcracking. The results of this test are given in column 7, Table 9.

TAB LE 9 Example Column No 1 NaX. 2 NaY.

We claim:

1. A process for preparing a catalyst composite which comprises forminga reaction mixture comprising:

(a) a matrix composed of at least two inorganic oxides wherein at leastone inorganic oxide is selected from the group consisting of siliceousoxides and aluminacontaining oxides, with the proviso that the siliceousoxide be present in amounts no greater than 90 weight percent, based onthe weight of the matrix, and any alumina-containing oxide be present inamounts of at least 10 weight percent, based on the weight of thematrix;

(b) a steam-unstable, base exchangeable crystalline metalaluminosilicate having pore openings greater than 6 and less than 15angstrom units in diameter, and containing greater than 4 weight percentalkali metal, said aluminosilicate being present in an amount less than60 percent by weight, based on the final composite; and

(c) a compound of a polyvalentmetal;

and thereafter heating said recation mixture in the presence of steam attemperatures of at least 800 F. for at least one-half hour in order toreduce the exchangeable alkali metal content of the reaction mixture andto provide a catalyst composition having an exchangeable alkali metalcontent of not more than 0.6 weight percent as determined by baseexchange with an excess of 25 percent aqueous ammonium chloride solutionat 180 F. for 24 hours.

2. The process of claim 1 wherein at least one of the inorganic oxidesof the matrix is alumina present in an amount ranging from 15 to 55weight percent, based on total matrix.

3. The process of claim 2 wherein the matrix is a member selected fromthe group consisting of natural clay, chemically treated clay andcalcined clay.

4. The process of claim 2 wherein the matrix is a synthetic composite ofsilica and alumina having an alumina content of at least 25 weightpercent.

5. The process of claim 2 wherein the aluminosilicate is an alkali metalaluminosilicate which is present in an amount less than 25 weightpercent, based on the final composite.

6. The process of claim 2 wherein the aluminosilicate has thecrystallographic structure of faujasite.

7. The process of claim 2 wherein said compound is a salt of rare earthmetal.

8. The process of claim 3 wherein the aluminosilicate has thecrystallographic structure of faujasite.

9. The process of claim 3 wherein the matrix is a clay of the kaolinitegroup.

10. The process of claim 9 wherein the aluminosilicate has thecrystallographic structure of faujasite.

11. The process of claim 9 wherein the catalyst composition has anexchangeable alkali metal content of not more than 0.4 weight percent.

12. The process of claim 2 wherein said compound is a compound of ametal of the group consisting of rare earths aluminum, calcium,magnesium and manganese.

13. The process of claim 10 wherein said compound is a rare earth salt.

References Cited UNITED STATES PATENTS 3,257,310 6/1966 Plank et a1.208-120 DANIEL E. WYMAN, Primary Examiner C. F. DEES, Assistant ExaminerU.S. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,459,679 August 5 1969 Charles J. Plank et a1.

It is certified that error appears in the above identified patent andthat said Letters Patent are hereby corrected as shown below:

Column 7 line 42 "120 O/F." should read 1200 F.

line 55, "dired" should read dried Column 11, Table 4, line 11, "1.12"should read 1.02 same table, line 23, "0.11" should read 0.01 Column 13,line 10, "11.5" should read 114.5 Column 14, line 7, after "246.2

grams insert of this product was impregnated under vacuum with line 44,"9000" should read 900 Column 15, line 56, "hurs" should read hoursColumn 16, line 67, "recation" should read reaction Signed and sealedthis 5th day of May 1970.

(SEAL) Attest: Edward M. Fletcher, Jr. WILLIAM E. SCHUYLER, JR

Attesting Officer Commissioner of Patents

